Iran on Monday confirmed it had accidentally sunk one of its own naval vessels, killing 19 Iranian sailors and injuring 15 others.
The "friendly fire" incident occurred Sunday in the waters of Jask and Chabahar during a training exercise in which the support ship Konarak was struck by an anti-ship missile, the BBC reported.
Iran's navy said in a statement on Monday that the accident had resulted in the "martyrdom of a number of brave members of the naval forces."
The Middle Eastern nation was widely criticized in January when it admitted to unintentionally shooting down a Ukrainian airliner, after first claiming the plane had gone down due to mechanical failure.
The January incident came amid escalating tensions with the United States, following the killing of Iranian military forces leader Qassem Soleimani in an attack ordered by President Donald Trump.
Trump has on various occasions warned Iran about the consequences of attacking American troops.
"If Iran wants to fight, that will be the official end of Iran," Trump tweeted after friction between the two nations in May of last year. "Never threaten the United States again!"